The present invention relates generally to an apparatus for sealing the space between a missile or rocket and missile launch tube prior to and during launch of the missile to prevent or restrict the flow of recirculating exhaust gases into the tube area around the rocket itself.
Rockets, missiles or other exhaust-gas propelled vehicles are often stored in launch tubes or containers from which they are ejected on launch. The inner diameter or dimension of the launch tube or container is normally larger than the outside dimensions of the missile or vehicle. Thus seals have been proposed in the past to prevent leakage of exhaust gases into the space between the missile and launch tube during launch and to retain the pressure generated by the exhaust gases in the space behind the missile.
In U.S. Pat. No. 4,399,999 of Wold, for example, a segmented annular seal is provided between the outer diameter of the missile and the inner surface of the launch tube. The seal travels up the launch tube with the missile and will be ejected with it, resulting in debris around the launch tube. Also, this arrangement provides no protection of the base region of the missile.
U.S. Pat. No. 4,324,167 of Piesik shows a rear cover for a rocket launch tube which provides a seal between the tube and the rear end of the rocket. The cover is fixed at the bottom of the launch tube and protects the base of the rocket only prior to movement up the tube. Once the rocket starts to move up the tube on launch, the cover separates from the rocket and thus exhaust gases can escape while the base of the rocket is unprotected.